In recent years, as antennas for base stations in a mobile communication network and antenna devices of Wi-Fi communication apparatuses, multiband antennas that are capable of performing communication in a plurality of frequency bands for the purpose of securing communication capacity have been put in practical use.
An example of such multiband antennas is disclosed in PTL 1. A multiband antenna disclosed in PTL 1 is configured with a plurality of dipole antenna elements each of which is tuned to a different frequency band. The multiband antenna is configured by alternately arraying crossed-dipole antenna elements for high frequencies and crossed-dipole antenna elements for low frequencies on an antenna reflector. Further, the multiband antenna has central conductive fences placed between columns of antenna elements. The central conductive fences are configured to reduce mutual coupling between adjacent high frequency antenna elements and between adjacent low frequency antenna elements.